Hi, I can't figure out why perl crashes with the error "Substitution loop at" when a string gets to be about 1 G long, it works fine on smaller strings. 
#!/usr/bin/perl -w
use strict;

my $string;
 
while ( <> ) {
  $string .= $_;
}
 
$string =~ s/\s+//g;
 
print length($string), "\n";

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then make a file and boom 

perl -e 'for ( 0 .. 100000000 ) { print "1234567890\n" }' > ! /scratch
+/100m

./evince_oddness /scratch/100m

Substitution loop at ./evince_oddness line 10, <> line 100000001

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It works fine on like 700mb strings, so has me baffled as I'm not a regex initiate, err acolyte?

I do know it's an inefficient way to read the file, I'm using File::Slurp but wanted to simplify the problem.

Oh and it happens with 5.10.0 and 5.8.8 64bit linux and 32bit solaris vendor compiled and me compiled so I don't think I just built a wonky perl.

In reply to problem with long strings and regex by flummoxer

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